# Effects of Temperature, Ionic Strength and Humic Acid on the Transport of Graphene Oxide Nanoparticles in Geosynthetic Clay Liner

## TL;DR

This study examines how temperature, ionic strength, and humic acid affect the movement of graphene oxide nanoparticles through geosynthetic clay liners in landfills.

## Contribution

A novel experimental setup was developed to study the transport and retention of GONPs in GCL under varying environmental conditions.

## Key findings

- GONP mobility and sorption in GCL decreased with higher temperature and ionic strength but increased with humic acid.
- GCL retention of GONPs was more effective than other porous materials like glass beads and quartz sand.
- Deposition ratio of GONPs in GCL increased with ionic strength but decreased with humic acid.

## Abstract

With the wide application of graphene oxide nanoparticles (GONPs), a great amount of GONP waste is discarded and concentrated in landfills. It has been proven that GONPs have strong toxicity and could gather toxic substances due to their high adsorption capacity. GONPs will seriously pollute the surrounding environment if they leak through the geosynthetic clay liner (GCL) in landfills. To investigate various factors (temperature, ionic strength (IS) and humic acid (HA)) on the transport and retention of GONPs in the GCL, a self-designed apparatus was created and column tests were carried out. The experimental results show that GONPs could be transported through the GCL. The mobility and sorption ratio of GONPs in GCL decreased with an increase in temperature and IS, and increased with an increase in HA. The temperature had little effect on the deposition ratio of GONPs in the GCL. The deposition ratio of GONPs in the GCL increased with IS, and decreased with an increase in HA. The transport of GONPs in GCL, glass beads and quartz sand was compared, and the results show that the retention ability of the GCL is much better than other porous materials. The experimental results could provide significant references for the pollution treatment in landfills.